1. Field of the Invention
This invention lies in the field of control devices for traffic lights, so as to modify or change the program of lighting, whenever an emergency vehicle is approaching the intersection at which they are positioned.
More particularly, this invention is related to an apparatus and method of control of the traffic lights at a street intersection, during the time interval that an emergency vehicle is approaching the intersection, and has turned on a unidirectional radio transmitter directed towards the receiver at the intersection.
2. Description of the Prior Art
There is considerable art in this area of emergency control of traffic lights. Some of the systems are operated by acoustical signals from an emergency vehicle, others by light signals, and still others by radio signals. Some of the control systems provide a green light for the traffic approaching the intersection in the direction from which the emergency vehicle is approaching and red in other directions. Others have different systems for lighting the traffic lights and so on. However, the system of this invention is designed to provide the greatest protection to individuals and normal vehicle traffic, and to provide as clear a path as possible for the emergency vehicles, than those shown in the prior art.